As an example of an apparatus for storing large amounts of data, there is a library apparatus that loads and stores many tape cartridges. The library apparatus sequentially extracts tape cartridges stored therein and loads the tape cartridges into a recording/reproduction apparatus for reading data from or writing data to the tape cartridges. Normally, tape cartridges are installed on an installation shelf inside the library apparatus. The installation shelf has one or more racks fixed to the inside of the library apparatus and a detachable magazine that can be extracted from the library apparatus. One or more tape cartridges are installed in the magazine in an aligned manner. The tape cartridges are conveyed to a recording/reproduction apparatus or an installation shelf of a given destination by a cartridge conveying mechanism.
In a case of ejecting a cartridge from the library apparatus, the magazine in which the cartridge is installed is required to be extracted from the library apparatus. Further, in a case of installing a cartridge into the library apparatus, the magazine which is to hold the cartridge is required to be extracted from the library apparatus.
With a conventional library apparatus, after a magazine is completely installed inside the library apparatus, data for identifying the tape cartridges are obtained by scanning all of the tape cartridges with a cartridge conveying mechanism and reading data from barcode labels adhered to the backs of the tape cartridges (this operation is referred to as an “inventory operation”). This inventory operation requires more time to read barcode labels as the number of tape cartridges increase. This results in the increase of the time for the library apparatus to become operational.
Although there is a known method for reducing barcode reading time by having plural barcode readers placed at a door part of a library apparatus into which tape cartridges (magnetic tapes) are installed, this method requires barcode readers to be provided to all of the magazines. Thus, the number of barcode readers increases as the number of magazines for storing the tape cartridges increases. This leads to a problem of high manufacturing costs.